초록
<P><B>Abstract</B></P> <P>Efficient treatment of swine wastewater at a high rate would facilitate the development of a sustainable pig industry. In this study, to investigate methane fermentation and membrane filtration performance, an anaerobic membrane bioreactor was operated under mesophilic conditions for 207 days during four stages, with a hydraulic retention time (HRT) decreasing from 5 to 3, 2, and 1 day, and a changing of solid retention time/hydraulic retention time (SRT/HRT) ratio from 18,18 to 8 and 3.2. The results showed that a higher volumetric methane production of 1.63 L/(L·d) and a lower VFAs concentration (<200 mg/L at stable stage) could achieved when the HRT was 1 day and SRT/HRT ratio was only 3.2. The specific methanogenic activity slightly decreased under the shorter HRT, and with SRT/HRT shortening, hydrogenotrophic <I>Methanocorpusculum</I> tended to dominate in bulk sludge while acetoclastic <I>Methanosaeta</I> dominated in the biofilm. Membrane fouling was observed after 4 months with a flux decline and a significant increase in trans-membrane pressure. A serial cleaning test indicated that organic pollutants contributed highly to the membrane fouling.</P> <P><B>Highlights</B></P> <P> <UL> <LI> HRT was successfully reduced to 1 day in the AnMBR. </LI> <LI> The specific methanogenic activity decreased during the shortening of the HRT. </LI> <LI> The biofilm attached to the membrane had higher acetoclastic methanogens. </LI> <LI> Membrane fouling was almost completely removed by sodium hypochlorite. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>